Folding binoculars

Abstract

Folding binoculars in which left and right eyepiece frames, each carrying an eyepiece, are swingably supported in such a manner as to be able to open and close with respect to each other, and objective frames, each carrying an objective, are mounted on the eyepiece frames in such a manner as to be able to project from and retract into the eyepiece frames. When the eyepiece frames are swung open, the objective frames are projected to and fixed at the front portions of the eyepiece frames, thereby bringing the optical axis of the objectives into alignment with those of the eyepieces, and thereby rendering the binoculars usable. When the binoculars are not in use, they can be folded to form a compact structure by moving the eyepiece frames toward each other to close.

What is claimed is: 
     
       1. Folding binoculars, comprising: a left eyepiece frame formed by a wall which encloses a first cavity, and including a left eyepiece which is fixed in place relative to and forms a part of said wall and which has a left eyepiece optical axis which is fixed relative to said left eyepiece frame;   a right eyepiece frame formed by a wall which encloses a second cavity, and including a right eyepiece which is fixed in place relative to and forms a part of said wall and which has a right eyepiece optical axis which is fixed relative to said right eyepiece frame;   a support coupled to said left eyepiece frame and said right eyepiece frame for swingably supporting said left eyepiece frame and said right eyepiece frame relative to each other in such a manner as to be able to open and close said left eyepiece frame and said right eyepiece frame with respect to each other;   a left objective frame including a left objective lens fixed in place relative to said left objective frame and having a left objective optical axis which is fixed relative to said left objective frame;   a right objective frame including a right objective lens fixed in place relative to said right objective frame and having a right objective optical axis which is fixed relative to said right objective frame;   means coupling said left objective frame to said left eyepiece frame for retracting said left objective frame into said first cavity when said left eyepiece frame and said right eyepiece frame are closed with respect to each other and for projecting said left objective frame from said first cavity such that said left objective optical axis is aligned with said left eyepiece optical axis when said left eyepiece frame and said right eyepiece frame are open with respect to each other; and   means coupling said right objective frame to said right eyepiece frame for retracting said right objective frame into said second cavity when said left eyepiece frame and said right eyepiece frame are closed with respect to each other and for projecting said right objective frame from said second cavity such that said right objective optical axis is aligned with said right eyepiece optical axis when said left eyepiece frame and said right eyepiece frame are open with respect to each other.   
     
     
       2. Folding binoculars according to claim 1, further comprising projecting mechanisms provided with springs and accommodated within said objective frames, said objective frames being urged by the springs to project outward relative to a respective cavity. 
     
     
       3. Folding binoculars according to claim 1, wherein each of said eyepiece frames has a substantially right-triangular planar configuration whereby said eyepiece frames have a substantially rectangular planar configuration when said eyepiece frames have been swung toward to each other and are closed. 
     
     
       4. Folding binoculars according to claim 3, further comprising projecting mechanisms provided with springs and accommodated within said objective frames, said objective frames being urged by the springs to project outward relative to a respective cavity. 
     
     
       5. Folding binoculars comprising: a pair consisting of left and right eyepiece frames which are each provided with an eyepiece having an optical axis and which are swingably supported by a support and coupled to each other via said support in such a manner as to be able to be open and close with respect to each other, each of said eyepiece frames having a substantially right-triangular planar configuration whereby said eyepiece frames have a substantially rectangular planar configuration when said eyepiece frames have been swung toward each other and are closed, and a pair of objective frames which are each provided with an objective having an optical axis and are each mounted on each of said eyepiece frames in such a manner as to be able to project from and retract into the eyepiece frame, wherein said objective frames are projected to and fixed at respective front portions of said eyepiece frames when said eyepiece frames are swung open, the optical axes of said objectives and the optical axes of said eyepieces being aligned with a state in which said eyepiece frames are open. 
     
     
       6. Folding binoculars according to claim 5, further comprising projecting mechanisms provided with springs and accommodated within said objective frames, said objective frames being urged by said springs in a direction in which said objective frames project outward.